Hi Lee,
I have one of these BEATA<dot>TRANQVILITAS coins from London (also RIC 225) and 2 from Trier (RIC 305). Attached is a photo of one I bought from CNG.
RIC has a photo of Trier 305 on Plate IV showing the dot in the legend, but there is no mention of the dot in the text - not even a footnote. Die römische Münzserie Beata Tranquillitas in der Prägestätte Trier 321-323, by Dieter Alten and Carl-Friedrich Zschucke, shows one example of Trier RIC 306 with a dot in the legend (p. 31, #17) and one example of RIC 305 (p. 31, #5 in Alten's book), but there is no mention of the dot in the text. With your coin, I am now aware of 7 specimens from 2 mints with this legend variant. All are from c. 321 AD and show consular busts of Constantine. I have not seen this variant for Licinius or the sons.
Regards,
Brent Upchurch

There's obviously something going on here with these pellets. Yours and mine are not die matches yet the pellet is clearly deliberate. Incidentally your obverse legend break is interesting. Not in RIC and very late in the legend.